The Byrna SD,Self Defense, is the successor of the Byrna HD. It has been re-engineered for optimal performance. Powered by compressed air,CO2, the Byrna SD shoots .68 caliber round kinetic and/or chemical irritant projectiles that can disable a threat from up to 60-feet away. It is an incredibly powerful and non-lethal self-defense weapon. The Byrna SD is not classified as a firearm therefore does not require a permit or background check to own. Must be 18 or older to purchase. The Byrna SD Kinetic Kit comes in a protective, zippered carrying case with everything you need to get started: One (1) Byrna SD Launcher, Two (2) 5-Round Magazines, Two (2) Byrna 8-Gram CO2 Cartridges, Two (2) 5-Round Tube of Byrna Kinetic Projectiles, One (1) 5-Round Tube of Byrna Eco-Kinetic Projectiles, One (1) byrnanation Medallion.